Comment # 3 on bug 103383 from Bernhard Rosenkraenzer

This problem persists after fixing the backlight control problem (bug 100446).

Turning the backlight all the way to 0 suspends the display to a state from
which it will wake up by adjusting brightness -- but after "xset dpms force
off", nothing (xset dpms force on or adjusting brightness up) brings the
display back to life.